Grand Rapids, MI 49503 Frost Dates
49503, near Grand Rapids, MI: the frost window
The last spring frost here typically falls around 05/06, about 251 days from today. Fall's first freeze usually shows up around 10/10, roughly 157 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Grand Rapids in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Grand Rapids's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
05/06 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/23 and only about 1 year in 10 sees frost after that.
Grand Rapids against the rest of the dataset
At roughly 157 frost-free days, Grand Rapids places 33,192 of 40,283 ZIP codes in this dataset. Within MI, it ranks 683 of 1,153.
Learn more
Two guides worth reading on 49503: the frost range, on how to read the range around Grand Rapids's dates instead of trusting one, and local microclimates, on what one yard in Grand Rapids can differ from the 49503 normal.